Page 230 - Clinical Manual of Small Animal Endosurgery

218 Clinical Manual of Small Animal Endosurgery

pro-oestrus. At these times vesicles may form in the vagina and vestibule.
Ruptured vesicles appear as raised red swellings in the mucosa and must
be differentiated from lymphoid follicles seen as a result of chronic irrita-
tion or infection.

Vaginal polyps
Vaginal polyps may be a cause of persistent vaginal discharge. These may
be pedunculated leiomyomas or mucosal fibrovascular polyps. Larger
polyps may be extruded and appear as a large pale or red swelling at the
vulvar lips. Pedunculated polyps are removed using a radiosurgical
polypectomy snare passed through the instrument channel of the cysto-
scope. Alternatively a diode laser may be used. If the polyp is near the
vulva then it may be possible to exteriorise the pedicle through manual
traction and then ligate and excise the mass using an open technique.

Vaginal tumours
Leiomyomas may be found either in the vaginal or vestibular lumen or
distorting the normal shape of the vagina or vestibule from an extralu-
minal origin. These tumours are encapsulated, sessile and not easily
removed cystoscopically. An episiotomy is usually required.
Transmissible venereal tumours are found in many tropical and sub-
tropical areas of the USA, Africa and Europe and present as irregular,
ulcerated masses in the vagina, vestibule and vulva. Chemotherapy is the
treatment of choice.

Ectopic ureters
Ectopic ureters are a cause of incontinence in young bitches. More than
95% of ectopic ureters in the dog are intra-mural (Berent et al., 2008),
with ureters passing into the bladder wall at the normal position in the
trigone and then passing within the wall to open into the urethra, vesti-
bule or vagina. There may be multiple openings and some may not be
patent. It is therefore important to assess each case carefully to ascertain
the exact anatomy in each case. Normograde or retrograde contrast
urography, ultrasound and computed tomography may be used to help
ascertain the path and patency of the ureters, and also to assess the
ureters and kidneys for pathology not visible from the bladder lumen,
such as hydronephrosis and hydroureter (Samii et al., 2004). Ectopic
ureters are commonly associated with other lower urinary tract anoma-
lies such as urethral sphincter mechanism incompetence (USMI), para-
mesonephric remnants and hydroureter.
Ectopic ureters are easily seen during urethrocystoscopy (Figs 7.9 and
7.10), which provides the gold standard for diagnosis. Many appear as
slit-like openings into the urethra but some may be very large, making
distinction between the urethra and ureter difficult.